The art includes several examples of osteosynthesis systems, assemblies and components useful for connecting bones or portions of bones to each other. Several designs, for example, include plates that span the bones or portions of bones to be connected, and anchors that secure the plates to the bones or portions of bones. In one example, described in U.S. Pat. No. 8,454,667, a plate includes a hole extending between surfaces of the plate. A spring-loaded retaining element partially overlaps the hole to help prevent inadvertent backing out of a fastener disposed in the hole and bone. In another example, described in U.S. Pat. No. 7,727,266, a deflectable ring is included to prevent backing out of a fastener.
Despite these and other example, a need exists for improved osteosynthesis systems, assemblies and components.